Nonequilibrium fluctuations in boson transport through squeezed reservoirs

Abstract

We investigate the effect of quantum mechanical squeezing on the nonequilibrium fluctuations of bosonic transport between two squeezed harmonic reservoirs and a bosonic site. A standard full counting statistics technique based on a quantum master equation is employed. We derive a nonzero thermodynamic affinity under an equal temperature setting of the two squeezed reservoirs. The odd cumulants are shown to be independent of squeezing under symmetric conditions, whereas the even cumulants depend nonlinearly on the squeezing. The odd and even cumulants saturate at two different but unique values which are identified analytically. Under maximum squeezing of one bath, the saturation value of the cumulants is solely governed by other bath’s properties. Further, squeezing always increases the magnitude of the even cumulants in comparison to the unsqueezed case. The saturation values of the even cumulants become independent of squeezing as soon as one bath is squeezed to its limit. This is in contrast to what is observed for the odd cumulants. The even cumulants are symmetric with respect to exchanging the left and right squeezing parameters while the affinity is found to be antisymmetric.